1. Field of the Invention
The present invention relates to the liquid crystal display technology and more particularly to a liquid crystal display (LCD) panel and fabrication method for the same.
2. Description of Related Art
An LCD panel is widely used in various electronic display devices, such as a mobile phone, a personal digital assistant (PDA), a digital camera, a computer and a laptop. The electronic display devices are all use high resolution color displays. An LCD panel commonly includes a TN (Twist Nematic) display panel, a VA (Vertical Alignment) display panel, a MVA (Multi-domain Vertical Alignment) display panel or an IPS (In-plane switching) display panel. Wherein, the VA display panel has advantages of high aperture ratio, high resolution, and wide viewing angle such that the VA display panel has been widely used in the large-size liquid crystal display.
However, the VA display panel has not been widely used in the small-size liquid crystal display. As shown in FIG. 1, in a pixel structure of the conventional VA display panel, the pixel electrode 101 on the array substrate is usually designed as a fishbone shape and being divided into multiple domains to improve the viewing angle property. A common electrode 102 on the color filter substrate is a one-piece strip and transparent electrode. In an initial alignment of the liquid crystal molecules, the pixel electrode 101 having the fishbone shape is used for the alignment such that the liquid crystal molecules have multiple pretilt angles in different directions in order to improve the viewing angle characteristic. However, when using the pixel electrode 101 having the fishbone shape to drive the LCD panel to display, the middle area of the pixel electrode 101 generates two dark lines 201 and 202 which are perpendicular to each other as shown in FIG. 2. When the size of the display panel is smaller, the influence of the two dark lines 201 and 202 to the light transmittance is more significant. Therefore, the VA display panel is not suitable for a high resolution, small size, and portable display device.
To solve the above technical problem, the prior art usually utilizes a pixel structure shown in FIG. 3a and FIG. 3b in a small size VA display panel. In FIG. 3a, a display panel comprises an array substrate 31, a color filter (CF) substrate 32, and a liquid crystal layer 33 disposed between the array substrate 31 and the CF substrate 32. A pixel electrode 34 is disposed at a side of the array substrate 31 adjacent to the liquid crystal layer 33. A common electrode 35 is disposed at a side of the CF substrate 32 adjacent to the liquid crystal layer 33. As shown in FIG. 3b, the pixel electrode 34 does not have the fishbone shape structure. For performing the alignment of the liquid crystal molecules, a circular hole structure 351 is disposed on the common electrode 35 of the CF substrate 32. The circular hole structure 351 can generate a wedge-shape electric field such that the liquid crystal molecules can have multiple pretilt angles in different directions. In the pixel structure, the pixel electrode 34 on the array substrate 31 does not have the fishbone shape structure, a dark line is only generated at the location of the circular hole structure 351. Comparing to the conventional fishbone shape electrode, the present invention can avoid the light transmittance from decreasing because of the fishbone shape electrode. However, because the circular hole structure 351 is added at the CF substrate 32, an additional mask is required in the fabrication process to remove a portion of the electrode at the location of the circular hole structure 351 such that the cost is increased.